This disclosure relates to a fabric having ultraviolet radiation protection, and more specifically, to a fabric having ultraviolet (UV) radiation protection incorporated into the fabric. Further, this disclosure relates to a fabric having enhanced ability to resist degradation of the fabric. The disclosure also provides methods to provide enhanced resistance to color degradation of a fabric and enhanced resistance to fiber strength degradation of a fabric. This disclosure provides methods to provide enhanced resistance to fire of a fabric.
Ecological friendly fabrics or Eco-friendly fabrics are gaining in popularity and use in clothing. An Eco-friendly fabric may be a natural fiber such as cotton, hemp, or bamboo which has been grown in soil that has not been treated with pesticides for a number of years. Some examples of other Eco-friendly fabrics are organic cotton, sisal, a combination of hemp and recycled rayon, a combination of hemp and cotton, broadcloth, denim, linen, and a combination of bamboo and recycled rayon. Natural fibers, which may be derived from plants or animals, such as wool, angora, silk, alpaca, cashmere, and silk are also examples of Eco-friendly fabrics. Synthetic fabrics, which may be made from synthetic sustainable products, such as nylon, rayon, olefin, spandex, acrylic, and tencel are also examples of Eco-friendly fabrics.
To assist an individual in determining whether a garment has protection against ultraviolet radiation, a rating system has been developed. This rating system is known in the industry as the UPF (Ultraviolet Protection Factor) rating system. Clothing having a rating of UPF 50 are able to block out 98% of the sun's ultraviolet radiation. Further, by way of example, a garment having a rating of UPF 15-24 will only block out 93.3% to 95.9% of ultraviolet radiation. Exposure to the sun's harmful ultraviolet radiation (known as UVA/UVB rays) can damage the skin, can cause sunburn, and can lead to skin cancer over prolonged exposure.
There are a number of factors that affect the level of ultraviolet radiation protection provided by a fabric and the UPF rating. Some factors are the weave of the fabric, the color of the fabric, the weight of the fabric, the fiber composition of the fabric, the stretch of the fabric, moisture content of the fabric. If the fabric has a tight weave or a high thread count then the fabric will have a higher UPF rating. However, even though the fabric has a higher UPF rating, the fabric may be less comfortable because a tighter weave or higher thread count means that the fabric is heavy or uncomfortable to wear. Another factor that affects protection is the addition of chemicals such as UV absorbers or UV diffusers during the manufacturing process. As can be appreciated, some of the features that make a garment comfortable to wear also make the garment less protective. A challenge for a clothing manufacturer is to provide clothing having both protection from the sun and being comfortable to wear.
Ultraviolet light exposure causes degradation in natural and synthetic fabrics, mainly due to the breakage of the polymer chains. The smaller polymer chains have a lower mechanical strength which in turn significantly reduces the overall strength of the fibers or the fabric. In addition, the UV light can cleave or oxidize the dye molecules which results in the loss of color over time. Once fabric or clothing degrades over time, the fabric or clothing may have to be discarded due to the appearance of the fabric or clothing. Due to degradation of the fabric or clothing, the fabric or clothing may not have been worn for an acceptable period of time. If the clothing was expensive, being only able to wear the clothing for a short period of time will not be acceptable to the wearer or purchaser of the clothing. The wearer or purchaser may not purchase the same brand in the future due to the problem encountered with the previous purchase. It is also known that ultraviolet light exposure causes color degradation in natural and synthetic fabrics. Once the color or colors in fabric or clothing degrades, the fabric or clothing may have to be discarded due to the unacceptable appearance of the fabric or clothing.
Additives to fabric, such as TiO2, can absorb UV light to lower the photo-degradation of the polymer and dyes. However, upon absorption of the UV light, the surface of TiO2 particles become catalytically active due to production of an electron-vacancy pair. The produced electrons and radicals attack the polymer around the particle surface and cause it to cleave, which can propagate crack in the fiber. In fact, the surface photo-reactive property of TiO2 is successfully used to destroy pollutant molecules in the residential air purifiers. In the presence of moisture and oxygen, the photo-degradation activity of TiO2 further increases due to the participation of H2O and O2 molecules in the cleavage, oxidation, and hydrolysis of the polymer molecules. In view of this, treating a fabric with an additive such as TiO2 should be avoided in order to allow the fabric not to prematurely degrade.
Fabric and clothing are also known to be highly flammable. In order to reduce the flammability of fabric or clothing, a flame retardant product is applied to the fabric or clothing. However, a large amount of flame retardant product needs to be incorporated into the fabric or clothing to make the fabric or clothing effective in decreasing the flammability of the fabric or clothing. This may be acceptable for use in specialized clothing, such as clothing for a fireman, but is unacceptable for daily wear or clothing. Clothing having a large amount of flame retardant product in it may not sell due to the appearance or feel of the clothing. In this event, treating clothing with a large amount of flame retardant product may not occur.
Therefore, it would be desirable to provide a fabric that does not prematurely degrade, in both color and fiber strength, over time. It would also be advantageous to provide a fabric that incorporates enhanced resistance to fire or flames. It would also be desirable to provide a fabric that can be treated to protect an individual from the effects of the sun. Moreover, there is a need for a controllable process for attaching UV protection to a fabric after the fabric has been manufactured so that the treated fabric may be used to protect an individual from UV radiation and to enhance the resistance to degradation of the fabric. Furthermore, it would be advantageous to incorporate adequate protection in a garment, fabric, or textile to protect against exposure to UV radiation, to increase the UV resistance of a garment, fabric, or textile, or to enhance UV radiation absorption of a garment, fabric, or textile to protect an individual from UV radiation, and also to be able to enhance the resistance to degradation of the garment, fabric, or textile.